1. Technical Field
The invention relates to jacks for lifting loads, and more particularly to hydraulic toe jacks.
2. Related Prior Art
Toe jacks are used for lifting loads in general industrial applications such as the rigging of machinery, automotive maintenance and material handling, and in the maintenance of railroad rails and beds. A toe jack typically includes a base and a lifting surface or "toe" that is moveable to a retracted position wherein the toe is flush or closely spaced with the base. Because the toe can be positioned so as to be closely spaced to the base, toe jacks are well-suited for use in close quarters and in applications wherein the object to be lifted provides minimal clearance for the jack.
Toe jacks can be either hydraulically or mechanically operated and can be used to lift extremely heavy loads over a relatively small distance. Because of the mechanical advantages that can be realized by using hydraulic fluid as a medium for operating a toe jack, hand operable hydraulic toe jacks can be used to lift loads exceeding several tons. However, a toe jack that is subjected to such heavy loading, must contain and maintain relatively high hydraulic fluid pressures within the toe jack.